When an IP-based network is utilised for the transmission of certain quality-sensitive services, such as voice or video data, there is a need to prioritise this kind of traffic. Previously, IP networks could offer only a “best effort” quality of service, wherein no differentiation was made between traffic types within a network element and packets were routinely dropped in the event of congestion. More recently IP networks are offering some quality of service guarantees. One example is the differentiated service, which provides a so-called “soft Quality of Service” mechanism that adds some information to an IP packet header so that intermediate nodes in the network, such as routers, can handle these packets differently. However, the settings of these parameters are not standardised. Consequently the values used to indicate specific levels of quality of service differ from IP network to IP network.
In present-day systems the quality of service parameters are conventionally set at network end points, although these parameters can be changed at intermediate nodes if these are configured to do so. The problem with implementing such a solution is that all clients using the network need to know which quality of service settings apply in any particular network. This is particularly problematic in systems where mobile communication services incorporate an IP network, for example, in an unlicensed radio access network, as all mobile stations that may at some time connect to the network must know the applicable settings. A similar problem arises when several data services with different quality of service needs are offered. The configuration of all the clients becomes very burdensome. While manual configuration by each client is possible, this presupposes a certain skill and knowledge and is consequently error-prone and ultimately unreliable. Configuration of a mobile station could be achieved by the transmission of an SMS, however, this also requires some action by the end user, such as accepting the SMS and some system must be provided for dispatching the SMSs to the appropriate mobile stations.